RIC owners: Flats or Rounds?

Flatwound

Roundwound

I've owned my RIC for a year now(ain't they GREAT) and have only used roundwounds on it.
The last few days I've been listening to a lot of BEATLES cd's and I really like McCartney's tone he gets with his RIC using flatwounds.
To get to my question, I was wandering who uses flats, and who uses rounds?
If you've used both on your RIC, which do you prefer?
Thanks,
Tim

Nylon Filament flats here, I just got my RIC so these are the strings that came on the bass but I love them! They're much easier on the fingers and the nylon filament strings look very cool (they're black). I think after a couple months I'll put on some Thomastik-Infeld Powerbass strings to see which more I like but for now I'm content with my flats.

There are huge differences between the two. The short answer is that there was a really good article in Bass Player Magazine that discussed the differences between strings, and even rated dozens of different sets for different uses. Try to find the article. It can be found on the bassplayer website http://archive.bassplayer.com/index.htm

The name of the article is "All Wound Up - The Controversial World of String Design." You can access the article if you click on "Gear", then click on the link.

In the meantime, think about it like this: the strings you normally use, assuming they're roundwounds, have a rough texture: it's the windings around the core that create this texture. Now, consider those windings are actually flat on both the inside of the windings and the outside (where you feel when you touch them). This gives the strings a completely smooth feel, and changes the tone dramatically.

Going from rounds to flats will give you a smooth tone that tends to not accentuate the upper-end harmonics and treble response in the same way. Flats produce a sound that's often described as smoother than rounds, but lacking in the "piano-like" clarity.

It's very difficult to describe beyond that, and everybody has their own take on it. But I will say that there are also a lot of misconceptions about flats. Again, the article in Bass Player does a good job of debunking some of those myths.